1. Field of the Invention
This invention relates to magnetic tape cassettes, and more particularly to a method of assembling a VHS system video tape cassette.
2. Background Art
In general, a VHS system or BETA system video tape cassette has a guard panel for opening and closing the opening through which the tape is drawn, which opening is formed in the front part of the cassette. The guard panel has supporting shafts at its right and left end pieces so that the guard panel is swingable about the supporting shafts. More specifically, the guard panel is substantially U-shaped, and can swing about the supporting shafts which are pivotally engaged with the side walls of the cassette. In the VHS system video tape cassette, one of the supporting shafts is engaged with an integral hole formed in the upper case half, the other supporting shaft is engaged and inserted into a segmented hole formed between the upper and lower case halves when they are joined.
Accordingly, in assembling the VHS system tape cassette, the one supporting shaft (hereinafter referred to as "a first supporting shaft") must be inserted into the integral hole of the upper half case. Accordingly, the guard panel cannot be combined with the upper case half simply by moving it towards the upper case half in such a manner that it is in parallel with the upper case half. Therefore, this assembling work must be done manually. At a minimum, it has been impossible to completely automate the assembling work. Accordingly, in the step of combining the guard panel with the upper case half, for instance the guard panel is inclined with respect to the upper case half so that the first supporting shaft is inserted into the integral hole, and then the guard panel is swung to cause the second supporting shaft to fall into upper case half part of the segmented hole. In this operation, the mechanism for pushing rubs the guard panel, with the result that scratches are liable to be formed on the guard panel. This difficulty may be eliminated by a method of bonding a relatively soft material such as a piece of cloth or tape to the pushing mechanism. However, the relatively soft material may come off the pushing mechanism when it is used for a long period. That is, it is low in durability.